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AN458 APPLICATION NOTE

for supply sequencing and remote control ON-OFF.

THERMAL PROTECTION

The thermal protection function, operates when the junction temperature reaches 150°C; it acts directly on the

power stage, turning it immediately off.

The thermal protection is provided with hysteresis and therefore, after an intervention has occurred, it is neces-

sary to wait for the junction temperature to decrease of about 30°C below the intervention threshold.

APPLICATIONS

The L4963, thanks to the reduced external component count represents a very low cost effective solution in

many applications. In Fig.18 the complete typical application circuit is shown, where all the functions available

on the device are being used.

In fig.19 is shown the same application circuit for reduced filter capacitor count and its PCB. As evident the PCB

dimensions are reduced. Below we will describe the design procedure to follow and some suggestion regarding

the external components to use.

Figure 17.

Figure 18. Test and Application Circuit